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Field guide to marine inhabitants - Invertebrates

Photo Courtesy of “Volusia County Reef Research Dive Team”

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Range: Octopus vulgaris is found in tropical and temperate waters worldwide. They are abundant in the Mediterranean Sea, off the coast of Japan, and in the Eastern Atlantic in coastal waters at depths of 3 to 660ft (1-200m). Similar Species: The Caribbean Two-Spot Octopus (Octopus filosus) closely resembles the common octopus in general body shape, coloration, and skin texture which forms a reticulated pattern of patches and thin grooves. However, unlike the Common Octopus, Octopus filosus has a unique blue ring that creates a false eye marking, called an ocellus, below the true eye.

Identification: Octopus vulgaris, like all octopus, has 8 arms lined with suckers which aid in prey capture and adhering to substrates. They can reach lengths of up to 3 ft (1m) including arms. The skin of Octopus vulgaris contains special pigment cells called chromatophores (along with iridophores and leucophores) which allow the octopus to blend in with its surroundings by altering the concentration of four different colored pigments (black, orange, red, and yellow) within these cells. Light interference and reflectance is also altered by the iridophores and leucophores, respectively, to achieve a state of camouflage. Therefore, Octopus vulgaris can be found exhibiting several different skin patterns and colorations; however, it is often reddish-brown with frontal white spots. Note: Octopus vulgaris discard the remains of their prey (bivalves and crustaceans) into piles called middens just outside their lairs. These piles make it easier to spot an octopus lair and often the octopus itself. back to field guide main page